Two new species of the rotifer genus Testudinella (Rotifera, Monogononta, Testudinellidae), T. pseudobscura sp. nov. and T. quadrilobata sp. nov., are described from the intertidal zone of a brackish-water tidal river and a mangrove swamp on Qiao Island in the Pearl River estuary, Guangdong province, southern China. Both species belong to T. clypeata (Müller, 1786)T. obscura Althaus, 1957 group on account of possessing a proximal fulcrum opening, a slit-like foot opening and living in thalassic waters. The trophi of Testudinella zhujiangensis Wei, De Smet & Xu, 2010 are redescribed, and a key to the marine and brackish-water Testudinella species know to date is presented.